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It is known that the circumference of an isosceles triangle is 30 cm and the length of one side is twice the length of the other. Find the length of its three sides
30/5=6cm
6*2=12cm
6*2=12cm
The three sides of a triangle are 5:4:3 long. The circumference of the triangle is 48 / 5 cm. How many cm are its three sides?
5+4+3=12
Longest side = 48 / 5 ÷ 12 × 5 = 4cm
Shortest side = 48 / 5 ÷ 12 × 3 = 12 / 5 cm
Other side = 48 / 5 ÷ 12 × 4 = 16 / 5 cm
The side length ratio of a triangle is 3:4:5. It is known that the perimeter of the triangle is 48 cm, the perimeter of the triangle is 48 cm, and the longest side of the triangle How much is it?
Divided into 12 parts, 48 / 12 = 4cm
So the three sides are 12cm, 16cm and 20cm respectively
Maximum 20cm
Formulas for radius of inscribed circle and circumscribed circle of right triangle
1. The radius of the inscribed circle is r = (a + B-C) / 2. The radius of the circumscribed circle is r = C / 2Ab, which is the right angle edge respectively, and C is the inclined edge. Firstly, a formula is proposed: Area s = 0.5 * (a + B + C) * r, R is the radius of the inscribed circle. It is proved that it can be obtained only by connecting each vertex and the center of the inscribed circle. Let C be the inclined edge
An object with a mass of 0.2kg is placed on the horizontal rotary table, and the distance between the object and the rotating shaft is r = 0.1M. The object is connected with the rotating shaft with a thin rope, and the thin rope is just straightened What I want to ask is, why does the maximum static friction provide centripetal force when the rope has no tension, and why must it be the "maximum" static friction?
When the rope has no tension, if the angular velocity of the rotary table is small, the required centripetal force is provided by the static friction, and the static friction is less than the maximum static friction
With the increase of angular velocity, the static friction increases, when the angular velocity reaches a certain value ω At 0, the static friction reaches the maximum
If there is no rope, the angular velocity is greater than ω 0, the object will slide relative to the turntable!
Now, due to the existence of the rope, when the angular velocity is greater than ω At 0, the rope will pull
Angular velocity less than or equal to ω 0, the rope has no tension; Angular velocity greater than ω At 0, the rope has tension
In the carriage moving at a uniform speed along the horizontal direction, the object a with mass m placed on the table in the carriage is stationary relative to the table, then the object a is affected The direction of static friction? The answer is horizontal to the right, I don't understand. Why does constant velocity produce static friction?
In the carriage moving at a uniform speed along the horizontal direction, the object a with mass m placed on the table in the carriage is stationary relative to the table. At this time, the object is only subject to gravity and supporting force, and the two forces are balanced. It will not be subject to any friction forward, backward, left and right
You're right if you can't figure it out. Others can only say it wrong
RELATED INFORMATIONS
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- 2. Does the hand of an object moving at a uniform speed on the conveyor belt have the effect of friction,
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